Created attachment 29342[details]
New build of apacheJmeter.jar with updated UrlConfigGui.java
This seems like a duplicate of bug 52613. I tried the fix and it doesn't seem to be working.
I am still getting the error:
Response message: URLDecoder: Illegal hex characters in escape (%) pattern - For input string: "" "
Please assist.
Thanks in advance

Thanks,
Reading your log file, issue occurs while you are recording using HTTP Proxy server, right ?
Please attach Test Plan, it's the most important one to reproduce.
Attached jar is useless, you can obsolete it.
Can you try with next nightly build revision r1382138, I have just updated code to get more logs:
- https://builds.apache.org/job/JMeter-trunk/lastSuccessfulBuild/artifact/trunk/dist/
Read following instructions to install this version:
- http://jmeter.apache.org/nightly.html
Before doing so, change the following in jmeter.properties:
log_level.jmeter=DEBUG
log_level.jmeter.junit=DEBUG
log_level.jmeter.control=DEBUG
log_level.jmeter.testbeans=DEBUG
log_level.jmeter.engine=DEBUG
log_level.jmeter.threads=DEBUG
log_level.jmeter.testelement=DEBUG
log_level.jmeter.util=DEBUG
log_level.jmeter.util.classfinder=DEBUG
log_level.jmeter.test=DEBUG
log_level.jmeter.protocol.http=DEBUG
# For CookieManager, AuthManager etc:
log_level.jmeter.protocol.http.control=DEBUG
log_level.jmeter.protocol.http.proxy=DEBUG
Regards
Philippe

ok. I just took out that field and it still failed with same message. So it's not the data or that field.
I added a data write and here is what i collected:
<?xml version="1.0" encoding="UTF-8"?>
<testResults version="1.2">
<sample t="0" lt="0" ts="0" s="false" lb="Sample failed" rc="" rm="URLDecoder: Illegal hex characters in escape (%) pattern - For input string: &quot;&quot; &quot;" tn="" dt="" by="0"/>

Hello,
Thanks for feedback.
Did you read nightly build build instructions ?
If you use it we will have much more infos.
Download the _bin and _lib files
Unpack the archives into the same directory structure
The other archives are not needed to run JMeter.
Building JMeter

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